Develop Reference

JSON Reader issue: cannot access jsonData

I have a strange thing going on here: I am using a JSON reader within a store to fetch search results. After loading the store I receive data or error states (built together as a JSON, too). So in both ways I get a successfully response, so I have to check the JSON for myself to trap "error conditions". But I cannot access the jsonData property that shhould be a JSON object within the reader. Chrome tells me that:
I can access the applyDefaults though (it returns true in that case) but not the jsonData.
My code looks like this:
var result = searchStore.getProxy().getReader();
console.log(result.jsonData);
The output is "undefined". As you can see in the picture the jsonData object holds my JSON (with the isError property I wanted to access).
What I am doing wrong?

You need to think more async and think of the timing it takes for a request to return and when you are trying to get the jsonData. Instead of using console.log, set a breakpoint or use the debugger; statement so you can freeze the browser and walk through the code. You can then inspect variables and such to see what the object looks like.

Try to access your JSON data in a success callback, to make sure the data is gathered from the server.

Someone please tell me what is wrong with my $.parseJSON [javascript / jquery]

Here is my tested result. I run my app, I get the "Hello" alert. But I don't get "After parse JSON" alert.
When I comment out the var rstList = $.parseJSON(data); line, "After parse JSON" alert prompted correctly.
I have check many document and reference but couldn't find out what is wrong with my $.parseJSON(). Please advice, thank you.
//Show restaurant listing
$('#restaurantList').on("pagebeforecreate", function() {
$.getJSON("http://mydomain/api/restaurant", function( data ) {
alert('Hello');
var rstList = $.parseJSON(data);
alert('After parse JSON');
});
});

Contrary to what the name implies, $.getJSON doesn't give you some JSON but the result of the parsing.
From the documentation :
The success callback is passed the returned data, which is typically a
JavaScript object or array as defined by the JSON structure and parsed
using the $.parseJSON() method.
You data is already parsed, don't parse it.
BTW, as Niet commented, you should have looked at the console to have a little more information on the error halting your script's execution. See Using the console.

Because you are trying to parse a json object again. Which causes the error. $.getJSON
will return the json object. You dont need to parse it again

Working with JSON via GET requests in Javascript

I've built a php API that provides data in json output, I need to get the values via a get request to then plot as a graph on the page.
The front end web component in hosted on the same server as in the api in this basic structure:
index.php
graph.php
/api/
/api/src
/api/src/api.php
My current code in graph.php is as follows:
<script>
var myJson;
$.getJson('api/src/api.php/poll/results/current/13/', function(jd){
myJson = jd.AnswerCount.1;
});
document.getElementById('jsonhere').innerHTML = myJson; //just to test
</script>
The endpoint outputs data like the following:
{"AnswerCount":{"1":5,"3":1,"2":2,"4":1,"5":5,"6":3,"7":2}}
Which I need loaded into a key-value pair array,
1:5
3:1
2:2
4:1
...
to then be put into the graphing library.
How do I fix my code/write new code to do this? I'm pretty stuck here.
EDIT:
On a hunch I logged all the get requests via wireshark, and no request is ever sent to the url in question. Even with an empty function { } ? http://grab.kfouwels.com/pmgW

You can't use a number as an identifier, to access the 1 property you have to say [1] not .1
You have to use the variable containing your data, not x which hasn't been mentioned until you try to assign it somewhere
The A in Ajax stands for Asynchronous. You have to work with your data inside your callback since the function you pass to getJson won't be called until the HTTP response arrived but the line starting document.get will run as soon as the HTTP request has been sent.

Json object in jquery can't be read?

I am trying to read the finance info from the google page into a json object.
Code is below:
try {
$.getJSON("http://finance.google.com/finance/info?client=ig&q=NSE:GOLDBEES&jsoncallback=?",function(data){
alert(data);//var jsondata = data;
//jsonobj = $.parseJSON(jsondata);
//alert(jsonobj[0].id);
});
} catch(e) {
alert(e.toString());
}
However I keep getting this error all the time on firebug
invalid label
"id": "4052464"
Is there any way this info can be read. My ultimate goal is to create a windows 7 gadget that doesnt use server side scripting and can be used from any Windows 7 system.
Appreciate all the help.
John

Response isn't valid JSON (response is prefixed with //), so jQuery won't be able to parse it correctly anyway.
To solve change &jsoncallback=? to &callback=?
so
$.getJSON("http://finance.google.com/finance/info?client=ig&q=NSE:GOLDBEES&callback=?", function(data) {
alert(data)
});

The response from Google has two leading /'s, making the response invalid JSON... for some reason.
Because of this, you cannot use jQuery.getJSON, as it expects a JSON response. Instead, you should use jQuery.get, and parse the JSON yourself after removing the two leading slashes.
jQuery.get('http://finance.google.com/finance/info?client=ig&q=NSE:GOLDBEES&jsoncallback=?', function (string) {
var validJson = string.slice(2);
var obj = jQuery.parseJSON(validJSON);
// use obj
});
Two additional points:
No JSONP is being used, so you don't need the jsoncallback=? in your request URL
The Windows Sidebar has been retired, so you cannot publish you finished gadget to the official gallery.

Accessing JSON values with a variable

I'm trying to access JSON data with jQuery and grab a specific set of values based on a variable. I've done this before using [] but for some reason I can't figure out what is going wrong this time.
My JSON file (being read in by getJSON, and named jsonmaker.php) looks like this:
{"0107001":{"label":"Canada","x":"0","y":"0.34"},"0107002":{"label":"USA","x":"-0.16","y":"0.53"}}
I then have a function which is essentially this:
function addAttrib(attrib) {
$.getJSON("jsonmaker.php", function(data) {
alert(data[attrib].label);
}
}
But it keeps returning undefined. Any idea what I'm doing wrong? I've checked to make sure the var going to attrib is 0107001, no problems there.
Also, I know my JSON file is a php file so I could filter what's returned to match the attrib value, but I'm looking to develop something that can run purely on HTML and JS, so I could just pack the JSON file for the project and take it with me. No need for a web server w/ PHP etc.

The data access itself works for me:
var data = {"0107001":{"label":"Canada","x":"0","y":"0.34"},"0107002":{"label":"USA","x":"-0.16","y":"0.53"}};
var attrib = "0107002";
alert(data[attrib].label); // USA
Make sure that attrib remains untouched between the moment you call addAttrib() and the moment when the AJAX request completes and your anonymous callback function gets called.
Update: is this your real code? You have at least one syntax error:
function addAttrib(attrib) {
$.getJSON("jsonmaker.php", function(data) {
alert(data[attrib].label);
}); // <- Please note missing ");"
}

In my experience, $.getJSON() doesn't always return an object. Depending on the MIME type that the server returns along with the JSON, you might end up with a string instead of an object. Check what data contains. If it's a string, you must manually parse it using eval() (old style) or JSON.parse() (new browsers only).

try to list all properties from data, to have sure the data is being returned:
for (var p in data){
if (data.hasOwnProperty(p){
alert(data[p]);
}
}
It's not your solution but with this you can know how your data is coming.